[deliverable/linux.git] / drivers / block / rsxx / dev.c

/*
* Filename: dev.c
*
*
* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
*	Philip Kelleher <pjk1939@linux.vnet.ibm.com>
*
* (C) Copyright 2013 IBM Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/slab.h>

#include <linux/hdreg.h>
#include <linux/genhd.h>
#include <linux/blkdev.h>
#include <linux/bio.h>

#include <linux/fs.h>

#include "rsxx_priv.h"

static unsigned int blkdev_minors = 64;
module_param(blkdev_minors, uint, 0444);
MODULE_PARM_DESC(blkdev_minors, "Number of minors(partitions)");

/*
 * For now I'm making this tweakable in case any applications hit this limit.
 * If you see a "bio too big" error in the log you will need to raise this
 * value.
 */
static unsigned int blkdev_max_hw_sectors = 1024;
module_param(blkdev_max_hw_sectors, uint, 0444);
MODULE_PARM_DESC(blkdev_max_hw_sectors, "Max hw sectors for a single BIO");

static unsigned int enable_blkdev = 1;
module_param(enable_blkdev , uint, 0444);
MODULE_PARM_DESC(enable_blkdev, "Enable block device interfaces");


struct rsxx_bio_meta {
	struct bio	*bio;
	atomic_t	pending_dmas;
	atomic_t	error;
	unsigned long	start_time;
};

static struct kmem_cache *bio_meta_pool;

/*----------------- Block Device Operations -----------------*/
static int rsxx_blkdev_ioctl(struct block_device *bdev,
				 fmode_t mode,
				 unsigned int cmd,
				 unsigned long arg)
{
	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;

	switch (cmd) {
	case RSXX_GETREG:
		return rsxx_reg_access(card, (void __user *)arg, 1);
	case RSXX_SETREG:
		return rsxx_reg_access(card, (void __user *)arg, 0);
	}

	return -ENOTTY;
}

static int rsxx_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
	u64 blocks = card->size8 >> 9;

	/*
	 * get geometry: Fake it. I haven't found any drivers that set
	 * geo->start, so we won't either.
	 */
	if (card->size8) {
		geo->heads = 64;
		geo->sectors = 16;
		do_div(blocks, (geo->heads * geo->sectors));
		geo->cylinders = blocks;
	} else {
		geo->heads = 0;
		geo->sectors = 0;
		geo->cylinders = 0;
	}
	return 0;
}

static const struct block_device_operations rsxx_fops = {
	.owner		= THIS_MODULE,
	.getgeo		= rsxx_getgeo,
	.ioctl		= rsxx_blkdev_ioctl,
};

static void disk_stats_start(struct rsxx_cardinfo *card, struct bio *bio)
{
	generic_start_io_acct(bio_data_dir(bio), bio_sectors(bio),
			     &card->gendisk->part0);
}

static void disk_stats_complete(struct rsxx_cardinfo *card,
				struct bio *bio,
				unsigned long start_time)
{
	generic_end_io_acct(bio_data_dir(bio), &card->gendisk->part0,
			   start_time);
}

static void bio_dma_done_cb(struct rsxx_cardinfo *card,
			    void *cb_data,
			    unsigned int error)
{
	struct rsxx_bio_meta *meta = cb_data;

	if (error)
		atomic_set(&meta->error, 1);

	if (atomic_dec_and_test(&meta->pending_dmas)) {
		if (!card->eeh_state && card->gendisk)
			disk_stats_complete(card, meta->bio, meta->start_time);

		bio_endio(meta->bio, atomic_read(&meta->error) ? -EIO : 0);
		kmem_cache_free(bio_meta_pool, meta);
	}
}

static void rsxx_make_request(struct request_queue *q, struct bio *bio)
{
	struct rsxx_cardinfo *card = q->queuedata;
	struct rsxx_bio_meta *bio_meta;
	int st = -EINVAL;

	might_sleep();

	if (!card)
		goto req_err;

	if (bio_end_sector(bio) > get_capacity(card->gendisk))
		goto req_err;

	if (unlikely(card->halt)) {
		st = -EFAULT;
		goto req_err;
	}

	if (unlikely(card->dma_fault)) {
		st = (-EFAULT);
		goto req_err;
	}

	if (bio->bi_iter.bi_size == 0) {
		dev_err(CARD_TO_DEV(card), "size zero BIO!\n");
		goto req_err;
	}

	bio_meta = kmem_cache_alloc(bio_meta_pool, GFP_KERNEL);
	if (!bio_meta) {
		st = -ENOMEM;
		goto req_err;
	}

	bio_meta->bio = bio;
	atomic_set(&bio_meta->error, 0);
	atomic_set(&bio_meta->pending_dmas, 0);
	bio_meta->start_time = jiffies;

	if (!unlikely(card->halt))
		disk_stats_start(card, bio);

	dev_dbg(CARD_TO_DEV(card), "BIO[%c]: meta: %p addr8: x%llx size: %d\n",
		 bio_data_dir(bio) ? 'W' : 'R', bio_meta,
		 (u64)bio->bi_iter.bi_sector << 9, bio->bi_iter.bi_size);

	st = rsxx_dma_queue_bio(card, bio, &bio_meta->pending_dmas,
				    bio_dma_done_cb, bio_meta);
	if (st)
		goto queue_err;

	return;

queue_err:
	kmem_cache_free(bio_meta_pool, bio_meta);
req_err:
	bio_endio(bio, st);
}

/*----------------- Device Setup -------------------*/
static bool rsxx_discard_supported(struct rsxx_cardinfo *card)
{
	unsigned char pci_rev;

	pci_read_config_byte(card->dev, PCI_REVISION_ID, &pci_rev);

	return (pci_rev >= RSXX_DISCARD_SUPPORT);
}

int rsxx_attach_dev(struct rsxx_cardinfo *card)
{
	mutex_lock(&card->dev_lock);

	/* The block device requires the stripe size from the config. */
	if (enable_blkdev) {
		if (card->config_valid)
			set_capacity(card->gendisk, card->size8 >> 9);
		else
			set_capacity(card->gendisk, 0);
		add_disk(card->gendisk);

		card->bdev_attached = 1;
	}

	mutex_unlock(&card->dev_lock);

	return 0;
}

void rsxx_detach_dev(struct rsxx_cardinfo *card)
{
	mutex_lock(&card->dev_lock);

	if (card->bdev_attached) {
		del_gendisk(card->gendisk);
		card->bdev_attached = 0;
	}

	mutex_unlock(&card->dev_lock);
}

int rsxx_setup_dev(struct rsxx_cardinfo *card)
{
	unsigned short blk_size;

	mutex_init(&card->dev_lock);

	if (!enable_blkdev)
		return 0;

	card->major = register_blkdev(0, DRIVER_NAME);
	if (card->major < 0) {
		dev_err(CARD_TO_DEV(card), "Failed to get major number\n");
		return -ENOMEM;
	}

	card->queue = blk_alloc_queue(GFP_KERNEL);
	if (!card->queue) {
		dev_err(CARD_TO_DEV(card), "Failed queue alloc\n");
		unregister_blkdev(card->major, DRIVER_NAME);
		return -ENOMEM;
	}

	card->gendisk = alloc_disk(blkdev_minors);
	if (!card->gendisk) {
		dev_err(CARD_TO_DEV(card), "Failed disk alloc\n");
		blk_cleanup_queue(card->queue);
		unregister_blkdev(card->major, DRIVER_NAME);
		return -ENOMEM;
	}

	if (card->config_valid) {
		blk_size = card->config.data.block_size;
		blk_queue_dma_alignment(card->queue, blk_size - 1);
		blk_queue_logical_block_size(card->queue, blk_size);
	}

	blk_queue_make_request(card->queue, rsxx_make_request);
	blk_queue_bounce_limit(card->queue, BLK_BOUNCE_ANY);
	blk_queue_max_hw_sectors(card->queue, blkdev_max_hw_sectors);
	blk_queue_physical_block_size(card->queue, RSXX_HW_BLK_SIZE);

	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, card->queue);
	queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, card->queue);
	if (rsxx_discard_supported(card)) {
		queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, card->queue);
		blk_queue_max_discard_sectors(card->queue,
						RSXX_HW_BLK_SIZE >> 9);
		card->queue->limits.discard_granularity = RSXX_HW_BLK_SIZE;
		card->queue->limits.discard_alignment   = RSXX_HW_BLK_SIZE;
		card->queue->limits.discard_zeroes_data = 1;
	}

	card->queue->queuedata = card;

	snprintf(card->gendisk->disk_name, sizeof(card->gendisk->disk_name),
		 "rsxx%d", card->disk_id);
	card->gendisk->driverfs_dev = &card->dev->dev;
	card->gendisk->major = card->major;
	card->gendisk->first_minor = 0;
	card->gendisk->fops = &rsxx_fops;
	card->gendisk->private_data = card;
	card->gendisk->queue = card->queue;

	return 0;
}

void rsxx_destroy_dev(struct rsxx_cardinfo *card)
{
	if (!enable_blkdev)
		return;

	put_disk(card->gendisk);
	card->gendisk = NULL;

	blk_cleanup_queue(card->queue);
	card->queue->queuedata = NULL;
	unregister_blkdev(card->major, DRIVER_NAME);
}

int rsxx_dev_init(void)
{
	bio_meta_pool = KMEM_CACHE(rsxx_bio_meta, SLAB_HWCACHE_ALIGN);
	if (!bio_meta_pool)
		return -ENOMEM;

	return 0;
}

void rsxx_dev_cleanup(void)
{
	kmem_cache_destroy(bio_meta_pool);
}
Commit	Line	Data
8722ff8c	1	/*
	2	* Filename: dev.c
	3	*
	4	*
	5	* Authors: Joshua Morris <josh.h.morris@us.ibm.com>
	6	* Philip Kelleher <pjk1939@linux.vnet.ibm.com>
	7	*
	8	* (C) Copyright 2013 IBM Corporation
	9	*
	10	* This program is free software; you can redistribute it and/or
	11	* modify it under the terms of the GNU General Public License as
	12	* published by the Free Software Foundation; either version 2 of the
	13	* License, or (at your option) any later version.
	14	*
	15	* This program is distributed in the hope that it will be useful, but
	16	* WITHOUT ANY WARRANTY; without even the implied warranty of
	17	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	18	* General Public License for more details.
	19	*
	20	* You should have received a copy of the GNU General Public License
	21	* along with this program; if not, write to the Free Software Foundation,
	22	* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	23	*/
	24
	25	#include <linux/kernel.h>
	26	#include <linux/interrupt.h>
	27	#include <linux/module.h>
	28	#include <linux/pci.h>
	29	#include <linux/slab.h>
	30
	31	#include <linux/hdreg.h>
	32	#include <linux/genhd.h>
	33	#include <linux/blkdev.h>
	34	#include <linux/bio.h>
	35
	36	#include <linux/fs.h>
	37
	38	#include "rsxx_priv.h"
	39
	40	static unsigned int blkdev_minors = 64;
	41	module_param(blkdev_minors, uint, 0444);
	42	MODULE_PARM_DESC(blkdev_minors, "Number of minors(partitions)");
	43
	44	/*
	45	* For now I'm making this tweakable in case any applications hit this limit.
	46	* If you see a "bio too big" error in the log you will need to raise this
	47	* value.
	48	*/
	49	static unsigned int blkdev_max_hw_sectors = 1024;
	50	module_param(blkdev_max_hw_sectors, uint, 0444);
	51	MODULE_PARM_DESC(blkdev_max_hw_sectors, "Max hw sectors for a single BIO");
	52
	53	static unsigned int enable_blkdev = 1;
	54	module_param(enable_blkdev , uint, 0444);
	55	MODULE_PARM_DESC(enable_blkdev, "Enable block device interfaces");
	56
	57
	58	struct rsxx_bio_meta {
	59	struct bio *bio;
	60	atomic_t pending_dmas;
	61	atomic_t error;
	62	unsigned long start_time;
	63	};
	64
65	static struct kmem_cache *bio_meta_pool;
66
67	/----------------- Block Device Operations -----------------/
68	static int rsxx_blkdev_ioctl(struct block_device *bdev,
69	fmode_t mode,
70	unsigned int cmd,
71	unsigned long arg)
72	{
73	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
74
75	switch (cmd) {
76	case RSXX_GETREG:
77	return rsxx_reg_access(card, (void __user *)arg, 1);
78	case RSXX_SETREG:
79	return rsxx_reg_access(card, (void __user *)arg, 0);
80	}
81
82	return -ENOTTY;
83	}
84
85	static int rsxx_getgeo(struct block_device bdev, struct hd_geometry geo)
86	{
87	struct rsxx_cardinfo *card = bdev->bd_disk->private_data;
88	u64 blocks = card->size8 >> 9;
89
90	/*
91	* get geometry: Fake it. I haven't found any drivers that set
92	* geo->start, so we won't either.
93	*/
94	if (card->size8) {
95	geo->heads = 64;
96	geo->sectors = 16;
97	do_div(blocks, (geo->heads * geo->sectors));
98	geo->cylinders = blocks;
99	} else {
100	geo->heads = 0;
101	geo->sectors = 0;
102	geo->cylinders = 0;
103	}
104	return 0;
105	}
106
107	static const struct block_device_operations rsxx_fops = {
108	.owner = THIS_MODULE,
109	.getgeo = rsxx_getgeo,
110	.ioctl = rsxx_blkdev_ioctl,
111	};
112
113	static void disk_stats_start(struct rsxx_cardinfo card, struct bio bio)
114	{
fa573f72 GZ	115	generic_start_io_acct(bio_data_dir(bio), bio_sectors(bio),
fa573f72 GZ	116	&card->gendisk->part0);
8722ff8c	117	}
	118
	119	static void disk_stats_complete(struct rsxx_cardinfo *card,
	120	struct bio *bio,
	121	unsigned long start_time)
	122	{
fa573f72 GZ	123	generic_end_io_acct(bio_data_dir(bio), &card->gendisk->part0,
fa573f72 GZ	124	start_time);
8722ff8c	125	}
	126
	127	static void bio_dma_done_cb(struct rsxx_cardinfo *card,
	128	void *cb_data,
	129	unsigned int error)
	130	{
c206c709	131	struct rsxx_bio_meta *meta = cb_data;
8722ff8c	132
	133	if (error)
	134	atomic_set(&meta->error, 1);
	135
	136	if (atomic_dec_and_test(&meta->pending_dmas)) {
0ab4743e PK	137	if (!card->eeh_state && card->gendisk)
0ab4743e PK	138	disk_stats_complete(card, meta->bio, meta->start_time);
8722ff8c	139
	140	bio_endio(meta->bio, atomic_read(&meta->error) ? -EIO : 0);
	141	kmem_cache_free(bio_meta_pool, meta);
	142	}
	143	}
	144
	145	static void rsxx_make_request(struct request_queue q, struct bio bio)
	146	{
	147	struct rsxx_cardinfo *card = q->queuedata;
	148	struct rsxx_bio_meta *bio_meta;
	149	int st = -EINVAL;
	150
	151	might_sleep();
	152
66bc6003 PK	153	if (!card)
	154	goto req_err;
	155
4f024f37	156	if (bio_end_sector(bio) > get_capacity(card->gendisk))
3eb8dcaf PK	157	goto req_err;
3eb8dcaf PK	158
8722ff8c	159	if (unlikely(card->halt)) {
	160	st = -EFAULT;
	161	goto req_err;
	162	}
	163
	164	if (unlikely(card->dma_fault)) {
	165	st = (-EFAULT);
	166	goto req_err;
	167	}
	168
4f024f37	169	if (bio->bi_iter.bi_size == 0) {
8722ff8c	170	dev_err(CARD_TO_DEV(card), "size zero BIO!\n");
	171	goto req_err;
	172	}
	173
	174	bio_meta = kmem_cache_alloc(bio_meta_pool, GFP_KERNEL);
	175	if (!bio_meta) {
	176	st = -ENOMEM;
	177	goto req_err;
	178	}
	179
	180	bio_meta->bio = bio;
	181	atomic_set(&bio_meta->error, 0);
	182	atomic_set(&bio_meta->pending_dmas, 0);
	183	bio_meta->start_time = jiffies;
	184
0ab4743e PK	185	if (!unlikely(card->halt))
0ab4743e PK	186	disk_stats_start(card, bio);
8722ff8c	187
	188	dev_dbg(CARD_TO_DEV(card), "BIO[%c]: meta: %p addr8: x%llx size: %d\n",
	189	bio_data_dir(bio) ? 'W' : 'R', bio_meta,
4f024f37	190	(u64)bio->bi_iter.bi_sector << 9, bio->bi_iter.bi_size);
8722ff8c	191
	192	st = rsxx_dma_queue_bio(card, bio, &bio_meta->pending_dmas,
	193	bio_dma_done_cb, bio_meta);
	194	if (st)
	195	goto queue_err;
	196
	197	return;
	198
	199	queue_err:
	200	kmem_cache_free(bio_meta_pool, bio_meta);
	201	req_err:
	202	bio_endio(bio, st);
	203	}
	204
	205	/----------------- Device Setup -------------------/
	206	static bool rsxx_discard_supported(struct rsxx_cardinfo *card)
	207	{
	208	unsigned char pci_rev;
	209
	210	pci_read_config_byte(card->dev, PCI_REVISION_ID, &pci_rev);
	211
	212	return (pci_rev >= RSXX_DISCARD_SUPPORT);
	213	}
	214
8722ff8c	215	int rsxx_attach_dev(struct rsxx_cardinfo *card)
	216	{
	217	mutex_lock(&card->dev_lock);
	218
	219	/* The block device requires the stripe size from the config. */
	220	if (enable_blkdev) {
	221	if (card->config_valid)
	222	set_capacity(card->gendisk, card->size8 >> 9);
	223	else
	224	set_capacity(card->gendisk, 0);
	225	add_disk(card->gendisk);
	226
	227	card->bdev_attached = 1;
	228	}
	229
	230	mutex_unlock(&card->dev_lock);
	231
	232	return 0;
	233	}
	234
	235	void rsxx_detach_dev(struct rsxx_cardinfo *card)
	236	{
	237	mutex_lock(&card->dev_lock);
	238
	239	if (card->bdev_attached) {
	240	del_gendisk(card->gendisk);
	241	card->bdev_attached = 0;
	242	}
	243
	244	mutex_unlock(&card->dev_lock);
	245	}
	246
	247	int rsxx_setup_dev(struct rsxx_cardinfo *card)
	248	{
	249	unsigned short blk_size;
	250
	251	mutex_init(&card->dev_lock);
	252
	253	if (!enable_blkdev)
	254	return 0;
	255
	256	card->major = register_blkdev(0, DRIVER_NAME);
	257	if (card->major < 0) {
	258	dev_err(CARD_TO_DEV(card), "Failed to get major number\n");
	259	return -ENOMEM;
	260	}
	261
	262	card->queue = blk_alloc_queue(GFP_KERNEL);
	263	if (!card->queue) {
	264	dev_err(CARD_TO_DEV(card), "Failed queue alloc\n");
	265	unregister_blkdev(card->major, DRIVER_NAME);
	266	return -ENOMEM;
	267	}
	268
	269	card->gendisk = alloc_disk(blkdev_minors);
	270	if (!card->gendisk) {
	271	dev_err(CARD_TO_DEV(card), "Failed disk alloc\n");
	272	blk_cleanup_queue(card->queue);
	273	unregister_blkdev(card->major, DRIVER_NAME);
	274	return -ENOMEM;
	275	}
	276
8c49a77c PK	277	if (card->config_valid) {
	278	blk_size = card->config.data.block_size;
	279	blk_queue_dma_alignment(card->queue, blk_size - 1);
	280	blk_queue_logical_block_size(card->queue, blk_size);
	281	}
8722ff8c	282
	283	blk_queue_make_request(card->queue, rsxx_make_request);
	284	blk_queue_bounce_limit(card->queue, BLK_BOUNCE_ANY);
8722ff8c	285	blk_queue_max_hw_sectors(card->queue, blkdev_max_hw_sectors);
8722ff8c	286	blk_queue_physical_block_size(card->queue, RSXX_HW_BLK_SIZE);
	287
	288	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, card->queue);
b277da0a	289	queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, card->queue);
8722ff8c	290	if (rsxx_discard_supported(card)) {
	291	queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, card->queue);
	292	blk_queue_max_discard_sectors(card->queue,
	293	RSXX_HW_BLK_SIZE >> 9);
	294	card->queue->limits.discard_granularity = RSXX_HW_BLK_SIZE;
	295	card->queue->limits.discard_alignment = RSXX_HW_BLK_SIZE;
	296	card->queue->limits.discard_zeroes_data = 1;
	297	}
	298
	299	card->queue->queuedata = card;
	300
	301	snprintf(card->gendisk->disk_name, sizeof(card->gendisk->disk_name),
	302	"rsxx%d", card->disk_id);
	303	card->gendisk->driverfs_dev = &card->dev->dev;
	304	card->gendisk->major = card->major;
	305	card->gendisk->first_minor = 0;
	306	card->gendisk->fops = &rsxx_fops;
	307	card->gendisk->private_data = card;
	308	card->gendisk->queue = card->queue;
	309
	310	return 0;
	311	}
	312
	313	void rsxx_destroy_dev(struct rsxx_cardinfo *card)
	314	{
	315	if (!enable_blkdev)
	316	return;
	317
	318	put_disk(card->gendisk);
	319	card->gendisk = NULL;
	320
	321	blk_cleanup_queue(card->queue);
66bc6003	322	card->queue->queuedata = NULL;
8722ff8c	323	unregister_blkdev(card->major, DRIVER_NAME);
	324	}
	325
	326	int rsxx_dev_init(void)
	327	{
	328	bio_meta_pool = KMEM_CACHE(rsxx_bio_meta, SLAB_HWCACHE_ALIGN);
	329	if (!bio_meta_pool)
	330	return -ENOMEM;
	331
	332	return 0;
	333	}
	334
	335	void rsxx_dev_cleanup(void)
	336	{
	337	kmem_cache_destroy(bio_meta_pool);
	338	}
	339
	340